Role of polarization mode dispersion on modulational instability in optical fibers.

We introduce the theory of modulational instability (MI) of electromagnetic waves in fibers with random polarization mode dispersion. Applying a linear stability analysis and stochastic calculus, we show that the MI gain spectrum reads as the maximal eigenvalue of a constant effective matrix. In the limiting cases of small or large fluctuations, we give explicit expressions for the MI gain spectra. In the general configurations, we give the explicit form of the effective matrix and numerically compute the maximal eigenvalue. In the anomalous dispersion regime, polarization dispersion widens the unstable bandwidth. Depending on the type of variations of the birefringence parameters, polarization dispersion reduces or enhances the MI gain peak. In the normal dispersion regime, random effects may extend the instability domain to the whole spectrum of modulations. The linear stability analysis is confirmed by numerical simulation of the full stochastic coupled nonlinear Schrödinger equations.

High-order dispersion-managed solitons for dense wavelength-division multiplexed transmissions.

Optimal dense wavelength-division multiplexed transmission is obtained based on high-order periodic dispersion-managed solitons in a dispersion-slope-compensated fiber link.

Dark-soliton-like pulse-train generation from induced modulational polarization instability in a birefringent fiber.

Theory and experiments show that the nonlinear development of the modulational polarization instability of an intense light beam in a normally dispersive, low-birefringence optical fiber leads to ultrashort dark-soliton-like trains with repetition rates in the terahertz range in the polarization orthogonal to the pump.

Buildup of terahertz vector dark-soliton trains from induced modulation instability in highly birefringent optical fiber.

We present the experimental observation of generation of vector dark-soliton pulse trains with terahertz repetition rates in the normal dispersion regime of an optical fiber. The polarization solitons build up from induced cross-phase modulation instability of two orthogonal pumps in a highly birefringent fiber.

Demonstration of a nonlinear gap in the modulational instability spectra of wave propagation in highly birefringent fibers.

We investigate modulational instability in normally dispersive highly birefringent fibers. By means of a technique based on a two-frequency pump field we are able to provide evidence for strong nonlinear dependence of the modulational instability spectra. This dependence manifests itself by the appearance of a nonlinear spectral gap in which modulational instability vanishes.